The present proposed details an approach to the total synthesis of maytansine, a tumor inhibitory substance. A covergent synthesis is outlined based on the coupling of a C1-C9 fragment with a C10-C18 synthon to complete the carbon framework. Specific objectives of this proposal include (1) the design of new lactam-forming reactions, (2) a new synthesis of a C1-C9 intermediate, (3) stereospecific synthesis of a C10-C18 intermediate, (4) design of a "linchpin" coupling reaction, (5) planning strategic alternatives to (2) and (3), and (6) preparation of structural analogs. The versatility of the primary and each alternate synthetic scheme is discussed, especially with regard to the preparation of structural analogs for clinical testing.